{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "Metal - pernitride compounds belong to a class of chemical systems in which both the complex ions and the non - bonding electrons may play roles in the formation of their modified crystalline structures ."}
{"Chemical": ["Metal - pernitride"]}